基于自适应陷波器的变频电源频率检测方法

An ANF-Based Frequency Detection Method for Variable-Frequency Power Supply

变频航空电源系统中,基波频率变化范围为360～800Hz,其频率检测方法需要具有频率自适应性来满足基波频率的大范围变化。基于自适应陷波器(ANF)的频率检测方法虽然能够在变频环境下提取出基波频率,但是其动态性能会受到基波频率的影响。本文首先针对采用不同结构的基于ANF的频率检测方法,对其动态性能进行了理论分析和实验测试,结果表明基于ANF的频率检测动态响应速度不仅与ANF的结构相关,而且与基波频率呈反比关系,当电源频率越高时,频率检测动态性能越差。然后针对不同结构的ANF频率检测方案,提出了一种通用的改进方法,将频率检测结果的平方值引入到频率检测单元中。该改进方法可以使得频率检测响应速度与电源频率呈正比关系,频率越高时,检测响应速度越快。在不同的电源频率下,都能在固定个电源周期内检测出频率信息,而且可以消除不同ANF结构对响应速度的影响。实验结果表明了文中分析结论和所提改进方法的正确性。

The fundamental frequency of aircraft power system varies from 360～800Hz. The frequency detection method for this application needs to overcome such large frequency variation. Although the frequency detection method based on adaptive notch filter（ANF） can extract the fundamentel frequency properly, the dynamical response is affected by the line fundamental frequency. The dynamical response of three ANF structures are analyzed first in this paper, theoretical and test results show that the dynamics of ANF is not only related to the ANF structure, but also related to the line frequency. The higher the line frequency, the longer the dynamical response time. Such property of ANF is not desirable for practical application. Then an improved frequency detection method based on ANF is proposed to overcome this problem, and it is general to all the three ANF structure discussed in this paper. The improved method can increase the dynamical response speed with higher line frequency. The experimental results verify the theoretical analysis and the proposed method.